.\"	$OpenBSD: BN_set_negative.3,v 1.4 2018/03/23 00:09:11 schwarze Exp $
.\"
.\" Copyright (c) 2016 Ingo Schwarze <schwarze@openbsd.org>
.\"
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.Dd $Mdocdate: March 23 2018 $
.Dt BN_SET_NEGATIVE 3
.Os
.Sh NAME
.Nm BN_set_negative ,
.Nm BN_is_negative
.Nd change and inspect the sign of a BIGNUM
.Sh SYNOPSIS
.Ft void
.Fo BN_set_negative
.Fa "BIGNUM *b"
.Fa "int n"
.Fc
.Ft int
.Fo BN_is_negative
.Fa "const BIGNUM *b"
.Fc
.Sh DESCRIPTION
.Fn BN_set_negative
sets
.Fa b
to negative if both
.Fa b
and
.Fa n
are non-zero, otherwise it sets it to positive.
.Pp
.Fn BN_is_negative
tests the sign of
.Fa b .
It is currently implemented as a macro.
.Sh RETURN VALUES
.Fn BN_is_negative
returns 1 if
.Fa b
is negative or 0 otherwise.
.Sh SEE ALSO
.Xr BN_add 3 ,
.Xr BN_new 3 ,
.Xr BN_set_bit 3 ,
.Xr BN_zero 3
.Sh HISTORY
.Fn BN_set_negative
and
.Fn BN_is_negative
first appeared in OpenSSL 0.9.8 and have been available since
.Ox 4.5 .
